Income Taxes (Schedule of Deferred Tax Assets and Liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Components of Deferred Tax Assets [Abstract]
Capital loss carryforward	$ 666	$ 1,009
Intangibles	37,634	33,542
Employee benefits and insurance claims accruals	6,307	12,146
Accounts receivable reserve	849	908
Inventory	631	0
Employee stock-based compensation	8,093	8,440
Accrued expenses not deductible for tax purposes	453	1,391
Accrued revenue not income for book purposes	695	429
Domestic net operating loss carryforwards	84,853	84,782
Foreign net operating loss carryforward	3,909	2,562
Deferred Tax Assets, Gross	144,090	145,209
Deferred Tax Assets, Valuation Allowance	(18,627)	(1,504)
Components of Deferred Tax Liabilities [Abstract]
Property and equipment	(142,965)	(199,532)
Total deferred tax liabilities	$ (17,502)	$ (55,827)